Vehicular exterior rearview mirror assembly with actuator

ABSTRACT

A vehicular exterior rearview mirror assembly for large vehicles, such as trucks, includes a reflective element, a support bracket, and an actuator mounting the reflective element to the support bracket. A mirror housing is secured to the support bracket. The electrical actuator is mounted to the support bracket by a plurality of fasteners and includes an actuator housing, which has a peripheral surface extending around the fasteners. The support bracket provides bearing contact for at least a portion of the peripheral surface of the housing to reduce the vibration and improve the stability of the mirror assembly. The electrical actuator includes a movable member which supports the reflective element for movement therewith and which extends into the actuator housing and frictionally engages the housing to minimize vibration of the movable member when it pivots. The electrical actuator preferably includes a biasing member to enhance the friction between the movable member and the housing to further reduce the vibration of the movable member and, therefore, the reflective element supported thereon.

This application claims priority from provisional application entitledVEHICULAR EXTERIOR REARVIEW MIRROR ASSEMBLY WITH ACTUATOR, Ser. No.60/154,137, filed Sep. 15, 1999, which is herein incorporated byreference in its entirety.

TECHNICAL FIELD AND BACKGROUND OF THE INVENTION

The present invention relates to rearview mirror assemblies for largevehicles and, more particularly, to exterior rearview mirror assemblieswith actuators which provide for adjustment of the reflective elementfor use on large vehicles, such as trucks, semi-trucks, vans, and thelike.

Conventional exterior rearview mirror assemblies for trucks, vans andother large vehicles include a support bracket, a mirror housing whichis mounted to the support bracket, a reflective element which issupported by the support bracket, and mirror mounting posts which extendfrom the support bracket for mounting the mirror assembly to supportarms or mounting brackets on the vehicle. In other mirror assemblies,the actuator may be mounted directly to the housing. More recently theselarge vehicle exterior rearview mirror assemblies also includeelectrically operated actuators which support the reflective element onthe support bracket or housing and provide remote adjustment of thereflective element.

In such larger vehicles, the suspension systems are usually much stifferand less resilient than on most passenger vehicles. Furthermore, manytrucks and vans have diesel engines which exhibit high vibration levels.As a result these larger vehicles induce relatively high base-levelvibrations in the exterior mirror assemblies which they carry. Oftenthis vibration is amplified by the vibration characteristics of themirror assembly itself and, further, by the less-than-rigid mountingarrangements for the mirror assemblies often associated with largervehicles.

One component that has an impact on the vibration of mirror assemblies,in general is the actuator. Trucks and vans often have large reflectiveelements on the order of at least 50 square inches. With increases inthe size of the reflective element, the size and weight of the actuatoralso increases. The increase in actuator weight is most significant inelectric actuators. Electric actuators add significant weight to amirror assembly, especially in these large mirror assemblies.Heretofore, these larger electric actuators also require specialmounting arrangements. For example, actuators available from Eaton ofThree Rivers, Mich. include three mounting holes which are centrallylocated on the base wall of the actuator housing rather than at theperiphery of the housing. As a result, these mounting arrangements arerelatively flexible. Furthermore, the manufacturers of the Eatonactuators require the actuators to be mounted on posts or bosses whichproject from the support bracket and require a minimum spacing betweenthe base wall of the actuator housing and the support bracket. Thisrequirement is designed to avoid deformations to the base wall when thefasteners, which secure the actuator, are tightened. Deformations in theactuator housing wall can lead to binding of the actuator. The largeractuators, therefore, exhibit significant vibration, and when coupledwith the inherent vibration of trucks, semis, vans and other largevehicles, often result in unacceptable vibration levels in thereflective element.

Therefore, there is a need for an exterior rearview mirror assembly,especially for large vehicles, which provides for remote adjustment ofthe reflective mirror element while minimizing the inherent vibrationcharacteristics of the mirror assembly so that acceptable vibrationlevels in the reflective element are maintained.

SUMMARY OF THE INVENTION

Accordingly, the present invention provides an improved, vehicularexterior rearview mirror assembly for vehicles, especially suitable forlarger vehicles, such as heavy trucks, vans and the like. The vehicularexterior rearview mirror assembly of the present invention provides anactuator mount with improved stiffness and rigidity resulting insignificantly reduced vibration and consequent image blurring in thereflective element. Further, the assembly has an increased naturalfrequency which prevents resonance in normal operating ranges of thesevehicles to help stabilize the mirror. The reduced vibration alsoreduces stress on any mirror arms or supports which attach the mirrorassembly to the vehicle.

In one form, the invention is a vehicular exterior rearview mirrorassembly for large vehicles, such as trucks, which includes a reflectiveelement, a support bracket, and an actuator mounting the reflectiveelement to the support bracket. A mirror housing is secured to thesupport bracket. The electrical actuator includes a housing with acentral portion and a peripheral portion extending around the centralportion, with the central portion being mounted to the support bracket.The assembly provides bearing contact for at least a portion of theperipheral surface of the housing and the support bracket to reduce thevibration and improve the stability of the mirror assembly.

In one aspect, the bracket includes a mounting surface and a resilientmember interposed between the mounting surface and the peripheralsurface of the actuator to provide the bearing contact. For example, theresilient member may comprise at least one resilient pad, which issecured to the support bracket. Preferably, the resilient pad is securedto the mounting surface of the support bracket, for example by anadhesive. The resilient pad preferably comprises a cellular urethane orequivalent type material. In other aspects, the resilient member has adurometer in a range of 12 to 18 Shore O.

In further aspects, the support bracket provides bearing contact for atleast 50% of the peripheral surface of the actuator, more preferablycontact for at least 75% of the peripheral surface of the actuatorhousing, and most preferably contact for approximately 100% of theperipheral surface. In other aspects, the support bracket includes anenlarged medial portion which is at least as large as the peripheralsurface of the housing to provide the bearing contact.

In yet other aspects, the electrical actuator housing includes a movablemember which extends into the housing and forms a friction contact withthe housing. The movable member provides adjustment for the reflectiveelement, with the frictional contact dampening the vibration of themovable member and reflective element. The actuator also includes abiasing member to urge the housing into frictional engagement with themovable member to thereby enhance the friction between the movablemember and the housing to further reduce vibration of the movable memberand of the reflective element. For example, the biasing member maycomprise a resilient ring, which extends around the actuator housing tourge the actuator housing into frictional engagement with the movablemember. Preferably, the resilient ring comprises a rubber elastic ring.

In another form of the invention, an exterior rearview mirror assemblyfor large vehicles, including trucks and vans, includes a one piececasing, a support bracket which extends between and is secured to theopposing end walls of the casing, a reflective element, and an electricactuator which supports the reflective element in the housing. Theelectric actuator is supported to the support bracket and includes anactuator housing having mounting openings for receiving fasteners, whichmount the actuator to the bracket, and a peripheral surface whichextends around the mounting openings. The support bracket providesbearing contact with at least a portion of the peripheral surface toprovide a rigid mounting with an electric actuator in the mirrorassembly.

In one aspect, the support bracket includes a medial portion which is atleast the size of the peripheral surface of the actuator housing. Forexample, the support bracket may include an adapter plate mountedthereto which provides the bearing surface for the actuator. The adapterplate may be formed from metal, such as cast aluminum or plastic. Inother aspects, the bracket further includes a gasket for providingbearing contact with the peripheral portion.

According to yet another form of the invention, an exterior rearviewmirror assembly for large vehicles, such as trucks and vans, includes areflective mirror element having a reflective surface of at least 50square inches, a support bracket which is adapted for mounting to avehicle, and a mirror casing which is secured to the support bracket.The mirror assembly further includes an actuator which is mounted to thesupport bracket by a plurality of fasteners, with the reflective mirrorelement being supported by the actuator in the casing. The actuatorincludes an actuator housing with a peripheral surface extending aroundthe fasteners, which mount the actuator to the bracket, with the supportbracket providing bearing contact for at least a portion of theperipheral portion surface of the housing whereby the mirror assemblyhas reduced vibration and improved stability. The actuator may, forexample, comprise an electric or manual hand set actuator.

In other aspects, the support bracket comprises an elongated truss-likesupport bracket and further includes an enlarged medial portion, withthe enlarged medial portion providing the bearing contact. Preferably,the enlarged medial portion is sized at least as large as the peripheralsurface of the housing.

Accordingly, the present invention provides a vehicular exteriorrearview mirror assembly for vehicles including trucks, semis, vans andthe like, which has reduced vibration and increased stability to provideclearer viewing images for the vehicle driver. The assembly includes animproved support bracket which provides a rigid support for the actuatorthereby improving the rigidity of the actuator mounting and the naturalfrequency of the mirror assembly.

These and other objects, advantages, purposes and features of theinvention will become more apparent from a study of the followingdescription taken in conjunction with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front, perspective view of a first embodiment of thevehicular exterior rearview mirror assembly of the present inventionhaving portions of the mirror element broken away to reveal the actuatorand internal support structure;

FIG. 2 is an exploded perspective view of the mirror assembly of FIG. 1with portions of the mirror assembly omitted for clarity;

FIG. 3 is an enlarged exploded perspective view of the support bracketand actuator shown in FIG. 1;

FIG. 4A is a cross-section view of the mirror assembly of FIGS. 1-3taken along line IVA—IVA of FIG. 1;

FIG. 4B is an enlarged cross-section view similar to FIG. 4Aillustrating the actuator and support bracket of FIGS. 1-4A;

FIG. 5 is an enlarged exploded perspective view of a second embodimentof the support bracket and actuator mounting;

FIG. 6 is an exploded perspective view of a third embodiment of thevehicular exterior rearview mirror assembly of the present invention;

FIG. 7 is an exploded perspective view of a fourth embodiment of thevehicular exterior rearview minor assembly of the present invention;

FIG. 8 is an enlarged perspective view of an adapter plate of thepresent invention; and

FIG. 9 is a side elevation view of an actuator mounted to the adapterplate of FIG. 9.

FIG. 10 is a side elevation view of an actuator.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring FIG. 1, the numeral 10 generally designates a vehicularexterior rearview mirror assembly of the present invention, which isespecially adapted for use on large vehicles, such as heavy trucks,semis, vans and the like. Mirror assembly 10 includes a reflectivemirror element 12, a support bracket 14, an actuator 16, and a casing orshell 18 supported by bracket 14. Casing 18 is preferably a one-piece,aerodynamically designed metal or plastic casing, which will be morefully described below.

As best understood from FIGS. 1 and 2, support bracket 14 spans theinterior space of the mirror casing 18 and extends from an upper wall 20to a lower wall 22 of casing 18 and includes a pair of mounting studs 24at its opposed ends which extend through casing 18 and are securedthereto by nuts 24 a and washers 24 b positioned at end walls 20, 22 formounting assembly 10 to a vehicle mounting bracket or mounting arms (notshown). Support bracket 14 is preferably an elongated, truss-typebracket, and more preferably sand or die cast from a lightweight metalor metal alloy, such as 319, 356 or 380 aluminum alloy or magnesium, andmay be, for example, electrostatically powder painted to provideincreased stiffness and rigidity with reduced weight. As best seen inFIGS. 3, 4A, and 4B, bracket 14 includes a pair of side members 15 a and15 b which are interconnected by a plurality of reinforcing webs 15 c(FIG. 4). Extending over side members and webs 15 a, 15 b, and 15 c is athin cover 15 d. For further details of one preferred embodiment ofbracket 14, reference is made to U.S. Pat. No. 5,721,646 to MichaelCatlin, the disclosure of which is incorporated by reference herein inits entirety.

Mirror element 12 is preferably a rectangular sheet or panel of glasshaving rounded corners, preferably having a thickness of 0.063-0.125inches. The size of reflective element 12 may vary but in large vehicleapplications, such as trucks or semis, preferably has an area of atleast 50 square inches and, most preferably, is 15″×7″. However, itshould be understood that other dimensioned reflective elements may beused and, further, that more than one reflective element, such asdisclosed in U.S. Pat. No. 5,721,646, may be used. A reflective coatingof a conventional chrome alloy or other metals or materials is appliedby conventional coating methods to the front and/or first surface ofmirror element 12, preferably providing reflection of at least about 55percent of the light incident thereon. Reflective element 12 ispreferably releasably mounted to actuator 16, for example, by a supportplate 12 a and mounting assembly 26 (FIG. 4A), which described in detailin U.S. Pat. No. 5,721,646. However, it should be understood that otherconventional mounting arrangements may be used. In addition, reflectiveelement 12 may include a resistive heating element or pad 12 bpreferably adhered to the rear surface of mirror element 12 or support12 a which when activated melts ice or snow that may have collected onthe surface of the mirror element. Reference is made to U.S. Pat. No.5,721,646 for further details of one suitable heating pad.

In the illustrated embodiment, actuator 16 comprises an electric motoractuator and provides adjustment of the position of mirror element 12 tovarious viewing positions about horizontal and vertical axes in responseto electrical signals generated by a remote control located in thevehicle cab or passenger compartment. Actuator 16 includes electricalwires or cables 16 a which project from actuator 16 and are harnessedwith other wiring, for example, wiring 12 c for heater pad 12 b, andother electrical or electronic devices in casing 18 and are directed outof casing 18 through an opening 52 a provided in rear wall 52 of casing18 for coupling to the electrical system of the vehicle. Actuator 16 ispreferably an electrically operated adjustable actuator of the type soldunder Model No. 530 by Eaton Corp. of Three Rivers, Mich. Electricalactuator 16 may also be of the type disclosed in U.S. Pat. Nos.4,101,206 and/or 4,116,538, the disclosures of which are herebyincorporated by reference herein. Alternately, actuator 16 may be of thetype disclosed in U.S. Pat. No. 4,281,899, the disclosure of which isalso incorporated by referenced herein. It should be understood thatactuator 16 may comprise a manual or remote manual actuator as well.

Referring to FIGS. 1 and 4A, actuator 16 supports reflective element 12on bracket 14 and is mounted to support bracket 14 in a manner to reducevibration and to increase stability of the overall assembly, as will bemore fully explained below. As best seen in FIG. 3, support bracket 14includes elongated body 36, which extends the entire length of thebracket and which includes curved or angled portions 38 for mountingbracket 14 to casing 18. Curved end portions 38 include end mountingflanges 40 each with an aperture 42 extending therethrough for receivingmounting studs 24. Each mounting flange 40 is reinforced by triangularshaped gusset plates 44. Thus, studs 24 extend through openings 42 andfurther through openings 20 a and 22 a provided in end walls 20, 22 ofcasing 18 and are secured therein by nuts 24 a and washers 24 b formounting assembly 10 on a vehicle mounting bracket or support arms.Extending outwardly and laterally from curved end portions 38 are pairsof mounting tabs or flanges 46 to which casing 18 is mounted usingfasteners 48 (FIG. 2). Tabs 46 are supported on rearward wall 52 bymounting bosses 54, which are reinforced by triangular shaped gussets 50formed on rearward facing wall 52 of casing 18. Each boss 54 includes atapered aperture 56 formed therein for receiving fasteners 48. In thismanner, casing 18 is rigidly mounting to bracket 14, which in turn isrigidly mounted to the respective vehicle mounting bracket or supportarms (not shown).

As shown in FIGS. 4A and 4B, support bracket 14 preferably providesbearing contact for actuator 16. As best seen in FIG. 4B, actuator 16includes a housing 30, a pair of electric motors 31 (only one shown)supported in housing 30, and rack and pinion gearing (not shown).Housing 30 includes a base 32 for mounting to support bracket 14, acover 33 for enclosing motors 31 and the rack and pinion gearing, and amovable member 34 to which reflective element 12 and support plate 12 aare mounted. Movable member 34 is pivotally mounted to housing 30 on atransverse arm 34 a and is driven to pivot about both x and y axes byrack and pinion gearing (not shown). Referring again to FIG. 3, basemember 32 includes an annular peripheral or perimeter portion 58 whichincludes a peripheral planar surface 58 a. Peripheral planar surface 58a extends around and is spaced outwardly toward bracket 14 from basewall 60 of base member 32. Base wall 60 includes a plurality of openings60 a (FIG. 2) through which fasteners 62 extend for securing actuator 16to support bracket 14. As best seen in FIGS. 2 and 3, at the medialportion of bracket 14 is a series of three upstanding securing posts ofbosses 64 which are interconnected and reinforced by walls 66. Each post64 includes a threaded opening 68 for receiving a respective threadedfastener 62 for securing actuator 16 to bracket 14. Posts or bosses 68are sized to extend to base wall 60 such that peripheral portion 58 ispreferably spaced approximately 0.7 mm±1.7 mm from upper surface 14 a ofbracket 14. Positioned between perimeter surface 58 and upper surface 14a of bracket 14 is a gasket 70. In the illustrated embodiment, gasket 70comprises a pair of resilient members or pads 72 which extendtransversely across upper surface 14 a of bracket 14. Preferably,resilient pads 72 have a durometer in a range of 12 to 18 Shore O. Inaddition, pads 72 preferably compress at least 10% but no more than 30%when actuator 16 is secured to bracket 14. In most preferred form, pads72 are compress approximately 20% and have a durometer of approximately18 Shore O. In preferred form, pads 72 comprise a PORON™ cellularurethane, which is commercially available under Part No.4701-50-15125-1604 from Grand Haven Gasket of Michigan which has adensity of approximately 20 lbs. per cubic foot, a maximum compressionof 20% at 70 C. and a durometer hardness of approximately 18 Shore O.Pads 72 are, further, preferably mounted to upper surface 14 a ofbracket 14 by an adhesive. It should be understood that pads 12 may beadhered to the peripheral surface 58 of actuator 16 instead. Preferably,pads 72 make bearing contact with at least 50% of the peripheral portion58 of actuator housing 30, more preferably, at least 75% of theperipheral portion, and in most preferred form approximately 100% of theperipheral portion. It should be understood that in order to increasethe contact area, the width of the bracket may be increased eitherlocally, as described in reference to the second embodiment, or over theentire length of the bracket. In this manner, when fasteners 62 extendthrough mounting openings 60 a and are secured in bosses 68, peripheralportion 58 will make bearing contact with and compress pads 72 ofbracket 14. As previously noted, pads 72 preferably compress at least10% but no more than 30% when fasteners are tightened. Pads 72 dampenthe vibration of actuator 16 which results in a substantially rigidmounting of actuator 16 on bracket 14. Furthermore, as best seen in FIG.4, upper surface 14 a of bracket 14 includes a recessed portion 14 b toaccommodate electrical housing member 74 which projects outwardly frombase wall 60 and peripheral portion 58 of actuator housing 30 andthrough which wires 16 a extend for coupling to the electrical system ofthe vehicle. By rigidly mounting actuator 16 to bracket 14, at leastover the resonant frequency range of the vehicle, the exterior rearviewmirror assembly's vibration characteristic is drastically improved andthe additional harmonics often produced by the actuator mounting areeffectively eliminated.

In order to further reduce the vibration characteristics of the actuator16 itself, actuator 16 includes a biasing member 80, which urges base 32into further frictional engagement with movable member 34. As best seenin FIGS. 3 and 4, movable member 34 includes an arcuate downwardlydepending wall 82 which extends between cover 33 and base 32. Base 32includes an upwardly extending annular rim 84 which includes a pluralityof elongated slots 86 which extend into an upper offset portion 88 ofrim 84. Biasing member 80 preferably extends around at least upperoffset portion 88 of rim 84 to bias rim 84 into frictional engagementwith the outer surface 82 a of arcuate wall 82 of movable member 34. Inthis manner, the friction between base member 32 and movable member 34is increased or enhanced to reduce the vibration of movable member 34and, therefore, reflective element 12. In addition, peripheral surface58 a is spaced inwardly of rim 84 so that the bearing forces on surface58 a from the mounting arrangement do not induce distortions in rim 84and, therefore, do not interfere with the movement of movable member 34.Biasing member 80 preferably comprises a resilient annular member, forexample, a wide rubber elastic band or ring. Biasing member 80 ispreferably a EPDM material, with a preinstalled diameter of 84.7 mm, anda 70 durometer EPDM material. Furthermore, shown in FIGS. 3 and 4B is aprotective rubber boot or cover 81 which extends between base 32 andmovable member 34 to protect actuator 16 from debris and moisture.

As shown in FIG. 5, a second embodiment 114 of exterior rearview mirrorassembly support bracket is illustrated. Like numerals are used toindicate like parts to those included in mirror assembly 10. Bracket 114is similar to bracket 14 but includes a modified elongated body 136.Elongated body 136 includes curved end portions 140 similar to bracket14 and an enlarged central portion 186, which provides bearing supportfor actuator 116, as will be more fully described below.

Similar to the previous embodiment, curved end portions 140 includemounting flanges 142 through which the mounting studs extend and furtherincludes mounting tabs 146 for securing the casing to bracket 114.Projecting outwardly from a medial portion of elongated body 136 are aplurality of mounting bosses 164 which are reinforced by walls 166, in asimilar manner to the previous embodiment. In this embodiment, however,mounting bosses 164 are sized such that when actuator mounting fasteners162 are extended through actuator housing 130, peripheral portion 158 ofactuator housing 130 contacts and bears on upper surface 114 a ofbracket 114 at enlarged portion 186. Furthermore, enlarged portion 186is preferably sized such that peripheral or perimeter portion 158 ofactuator housing 130 makes full contact with upper surface 114 a ofbracket 114. In addition, enlarged portion 186 preferably includes aplanar surface 186 a to assure a good interference fit between actuator116 and bracket 114. An interference fit is more suitable where bracket114 is made from precise casting. For example, permanent mold casting,such as steel mold casting, permits a more precise casting. In order toachieve the interference fit between actuator 116 and bracket 114, thepost or boss height must be controlled with greater precision to avoiddeformation or warpage of the actuator housing. For example, for IKUmodel 530, bosses 164 should have a height of approximately 18.7 mm,with a tolerance of ±0.3 mm. To accommodate electrical housing portion174 of actuator 116, upper surface 186 a of enlarged portion 186includes a recessed portion 186 b similar to recessed portion 14 b. Inthis manner, actuator 116 is rigidly mounted to support bracket 114 andthus exhibits reduced harmonics and, further, does not induce any addedvibration to the reflective element of the rearview mirror assembly. Itshould be understood as noted in reference to the first embodiment, thefull length of bracket 114 may be enlarged, or at least the portionbetween curved end portions 140. As described in reference to theprevious embodiment, bracket 114 preferably provides bearing contactwith at least 50% of peripheral surface 158, more preferably 70% ofperipheral surface 158, and most preferably approximately 100% ofperipheral surface 158.

Referring to FIG. 6, a third embodiment of mirror assembly 210 isillustrated. Mirror assembly 210 includes a casing 218 (shown inphantom), a reflective element 212 (shown in phantom), a support bracket214, and an actuator 216. Actuator 216 is of similar construction toactuator 16. Mirror assembly 210 further includes a fixed mountingbracket 215 a for directly mounting assembly 210 to the vehicle door orframe and also an extension arm 215 b to which support bracket 214 ismounted or formed therewith.

Similar to the first embodiment, support bracket 214 includes anelongated body 236, which extends between opposed end walls of themirror casing 218. In the illustrated embodiment, bracket 214 has atubular shaped body and, further, similar to the previous embodiments ispreferably a truss-like bracket or non-solid bracket to reduce theweight of the bracket. Projecting outwardly from mounting surface 214 aof elongated portion 236 are a plurality of mounting bosses or posts 264which are interconnected by reinforcing walls 266, in a similar mannerto the previous embodiments. Actuator 116 is mounted to mounting bosses264 by fasteners 262 which extend through openings 260 in actuatorhousing 30 and extend into corresponding threaded apertures 268 ofmounting bosses 264. Positioned between peripheral surface 258 ofactuator base 232 and upper surface 214 a of elongated body 236 are apair of resilient pads 272, which provide bearing support for actuator216 on bracket 214. Pads 272 are of similar construction to pads 72 and,therefore, reference is made thereto for further description of pads272.

It should be understood from the foregoing, that mounting bosses 264 maybe sized to permit an interference fit between actuator 216 and bracket214 and, further, elongated body 236 may include enlarged centralportions similar to bracket 114 to provide a 100% bearing contact withperipheral portion 258 or actuator housing 230 as described in referenceto bracket 114.

A fourth embodiment 310 of vehicular rearview mirror assembly of thepresent invention is illustrated in FIG. 7. Again, like numerals areused to indicate corresponding parts included in mirror assembly 10.Assembly 310 includes a casing 318, a reflective element 312, which issupported on a modified support bracket 314 by actuator 316. Further,assembly 310 includes mounting arms 319 a and 319 b which are formedwith or mounted to bracket 316 and are adapted to mount directly to thevehicle door panel or vehicle frame (not shown).

Bracket 314 includes an elongated body 336 and a reinforcing member orweb 337. Bracket 314 includes a plurality of mounting bosses 346 whichextend through web 337 and elongated body 336 for receiving fasteners(not shown) to secure casing 318 to mounting bracket 314. Similar to thefirst and third embodiments, an upper or mounting surface 314 a ofmounting bracket 314 includes a gasket in the form of resilient pads372, which are secured thereto by, for example, an adhesive, and providebearing contact between support bracket 314 and peripheral portion 358of actuator housing 330 to provide a rigid mounting of actuator 316 onsupport bracket 314. Reference is made to the first embodiment forfurther details of suitable resilient pads. It should be understood,from the foregoing, that support bracket 314 may be modified to providean interference fit similar to the second embodiment and, further, toinclude an enlarged contact area to provide approximately 100% bearingcontact with peripheral portion 358 similar to the second embodiment ofthe present invention.

Referring to FIG. 8, the numeral 415 generally designates an adapter ofthe present invention. Adapter 415 may be used in conjunction with anyof the previously described support brackets. As best seen in FIG. 8,adapter 415 includes a plate member 418 and a plurality of mountingbosses 420 which receive fasteners (not shown) for mounting adapter 415to a bracket, such as bracket 14. It should be understood, however, thatadapter 415 may also be used with brackets 114, 214, and 314.

In addition, adapter 415 includes a second plurality of mounting bosses464, which are reinforced by interconnecting walls 466, similar to theprevious embodiments. Mounting bosses 464 are similar to mounting bosses64, 164, 264, and 364 and receive fasteners for mounting actuator 416onto adapter 415 to thereby mount adapter to bracket 14, for example.Plate member 418 includes a planar bearing surface 418 a and ispreferably sized to contact effectively all of the available bearingsurface 458 a of actuator housing 430, with the exception of the bearingsurface adjacent the electrical housing 474 (FIG. 10). In order toaccommodate electrical housing 474, which projects outwardly fromhousing 430, plate member 418 includes a notched portion 418 a.

As will be understood from FIGS. 9 and 10, mounting bosses 464 are sizedsuch that bearing surface 418 a of plate member 418 makes direct contactwith annular surface 458 a of actuator housing 430. In this manner,adapter 415 provides an interference fit with actuator 430 and rigidlysupports actuator 430 in the respective mirror assembly, similar to theprevious embodiments. Adapter 415 may be formed from a metal, including,for example cast aluminum similar to bracket 14, or may comprise aplastic material, such as a reinforced polymer, such as reinforcednylon, or the like.

Accordingly, the present invention provides rearview mirror assembliesfor use on large vehicles which exhibit reduced vibration in thereflective element. This reduction in the vibration is achieved byimproving the vibration characteristics of the rearview mirror assemblyitself and by providing a bearing contact between at least a portion ofthe peripheral surface of the actuator housing and the support bracket.By controlling the height of the mounting bosses, the actuator may bedirectly mounted onto the mirror assembly support bracket to provide aninterference fit between the actuator housing and the mounting surfaceof the support bracket without warping the actuator housing base wall.Furthermore, existing mirror assemblies may be modified to achieve theclaimed invention by incorporating a gasket, such as the resilient padsdescribed in reference to the first, third, and fourth embodiments.While several forms of the invention have been shown and described,other forms will now become apparent to those skilled in the art. Forexample, while the resilient pads are illustrated as rectangulardiscrete pads, it should be understood that a single unitary pad may beprovided which includes cut-outs for the mounting bosses and reinforcingwalls. In addition, the concept of this invention may be used with otherconfigurations of support brackets, casings, and actuators. In addition,the number of mounting bosses may be increased as needed to accommodatevarying actuator mounting arrangements. Therefore, it will be understoodthat the embodiments shown in the drawings and described above aremerely for illustrative purposes only and are not intended to limit thescope of the invention which is defined by the claims which follow. Theembodiments of the invention in which we claim an exclusive property orprivilege are as follows.

The embodiments of the invention in which we claim an exclusive propertyor privilege are as follows:
 1. An exterior rearview mirror assembly forlarge vehicles, such as trucks and vans, said exterior rearview mirrorassembly comprising: a reflective mirror element; a support bracketbeing adapted for mounting to a vehicle; a mirror casing secured to saidsupport bracket; an actuator having an actuator housing and a movableportion for engaging said reflective element, said movable portionprovided at one side of said actuator housing, said actuator housinghaving a recessed central portion and a raised peripheral portion havinga planar surface extending around said central portion and facing saidbracket from said central portion and on an opposite side of saidactuator housing from said movable portion, said central portion of saidactuator housing being mounted to said support bracket, said reflectivemirror element being supported by said actuator, said casing providing ahousing for said support bracket, said actuator, and said reflectivemirror element; bearing contact being provided between said supportbracket and at least a portion of said planar surface of said actuatorhousing, said planar surface contacting said bearing contact wherebysaid assembly has reduced vibration and improved stability.
 2. Themirror assembly of claim 1, wherein said support bracket includes amounting surface and a resilient member interposed between said mountingsurface and said portion of said planar surface of said actuator housingto provide said bearing contact.
 3. The mirror assembly of claim 2,wherein said resilient member comprises at least one resilient pad, saidresilient pad being secured to said support bracket.
 4. The mirrorassembly of claim 3, wherein said resilient pad is secured to saidmounting surface by an adhesive.
 5. The mirror assembly of claim 2,wherein said resilient member compresses in a range of 10% to 30% whensaid actuator is mounted to said support bracket.
 6. The mirror assemblyof claim 3, wherein said resilient pad comprises a cellular urethanematerial.
 7. The mirror assembly of claim 2, wherein said resilientmember comprises a pair of resilient pads.
 8. The mirror assemblyaccording to claim 2, wherein said resilient member has a durometer in arange of approximately 12 to 18 Shore O.
 9. The mirror assembly of claim1, wherein said support bracket includes a corresponding plurality ofprojecting mounting bosses, said actuator being secured to said mountingbosses by fasteners.
 10. The mirror assembly of claim 1, wherein saidsupport bracket provides bearing contact for at least 50% of said planarsurface of said actuator housing.
 11. The mirror assembly of claim 10,wherein said support bracket provides bearing contact for at least 75%of said planar surface of said actuator housing.
 12. The mirror assemblyof claim 11, wherein said support bracket provides bearing contact forapproximately 100% of said planar surface.
 13. The mirror assembly ofclaim 12, wherein said support bracket includes an enlarged medialportion, said enlarged medial portion being at least as large as saidplanar surface of said housing and providing said bearing contact. 14.The mirror assembly according to claim 13, wherein said support bracketincludes an adapter mounted thereto, said adapter providing saidenlarged medial portion.
 15. The mirror assembly of claim 1, whereinsaid movable member extends into said housing and forms a frictioncontact with said housing, said movable member providing adjustment forsaid reflective element, and said actuator including a biasing member tourge said housing into said frictional engagement with said movablemember to thereby enhance the friction between said movable member andsaid housing to reduce vibration of said movable member and of saidreflective element.
 16. The mirror assembly of according to claim 14,wherein said biasing member comprises a resilient annular memberextending around said actuator housing to urge said actuator housinginto frictional contact with said movable member.
 17. The mirrorassembly according to claim 16, wherein said resilient annular membercomprises a rubber elastic ring.
 18. The mirror assembly according toclaim 1, wherein support bracket comprises an elongated support bracket.19. The rearview mirror assembly according to claim 1, wherein saidsupport bracket comprises a truss-type bracket.
 20. The mirror assemblyaccording to claim 19, wherein said support bracket includes a pair ofelongated side members and interconnecting webs extending between saidside members to form a rigid support bracket.
 21. The mirror assemblyaccording to claim 1, wherein said support bracket comprises a bracketcast from a material selected from the group consisting of aluminum,aluminum alloy, and magnesium.
 22. The mirror assembly of claim 1,wherein said mirror element comprises an electro-optic element adaptedto reduce the amount of reflected light when electric voltage is appliedto said element.
 23. The mirror assembly of claim 22, wherein saidmirror element comprises an electrochromic mirror element.
 24. Themirror assembly of claim 1, wherein said casing includes a rear wall anda peripheral rim spaced from said rear wall, said mirror element beingrecessed behind said peripheral rim toward said rear wall of saidhousing.
 25. The mirror assembly of claim 1, wherein said casingcomprises a one piece resinous plastic casing.
 26. The mirror assemblyof claim 1, wherein said casing comprises a metal casing.
 27. Anexterior rearview mirror assembly for large vehicles, including trucksand vans, said mirror assembly comprising: a one-piece casing havingopposing end walls and side walls and a rear wall; a support bracketextending between and being secured to said opposing end walls of saidcasing; a reflective mirror element; an actuator supporting saidreflective element in said housing, said actuator being mounted to saidsupport bracket, said actuator including an actuator housing and amovable portion for engaging said reflective element, said movableportion provided at one side of said actuator housing, said actuatorhousing having mounting openings extending therethrough for receivingfasteners and a planar raised peripheral surface extending around saidmounting openings and provided on an opposite side of said actuatorhousing from said movable portion; bearing contact being providedbetween said support and at least a portion of said peripheral surfaceof said actuator, and said at least a portion contacting said bearingcontact to provide a rigid mounting of said actuator in said mirrorassembly.
 28. The exterior rearview mirror assembly according to claim27, wherein said support bracket includes a medial portion being atleast the size of said peripheral surface of said actuator housing. 29.The mirror assembly according to claim 27, wherein said support bracketcontacts at least 50% of said peripheral surface of said actuatorhousing.
 30. The mirror assembly according to claim 29, wherein saidsupport bracket contacts at least 75% of said peripheral surface. 31.The mirror assembly according to claim 30, wherein said support bracketcontacts approximately 100% of said peripheral surface.
 32. The mirrorassembly according to claim 27, wherein said support includes anadapter, said adapter providing said bearing contact.
 33. The mirrorassembly according to claim 27, wherein said support bracket furtherincludes a gasket for providing bearing contact with said peripheralsurface.
 34. The mirror assembly according to claim 33, wherein saidgasket has a durometer in a range of 12 to 18 Shore O.
 35. The mirrorassembly according to claim 33, wherein said gasket comprises at leastone resilient pad interposed between said support bracket and saidperipheral surface.
 36. The mirror assembly of claim 27, wherein saidperipheral surface comprises an annular surface, said annular surfaceextending around said mounting openings and being spaced from saidopenings toward said support bracket.
 37. The mirror assembly accordingto claim 27, wherein said support bracket comprises a metal truss-likebracket.
 38. The mirror assembly according to claim 27, wherein saidsupport bracket comprises a cast metal support bracket.
 39. An exteriorrearview mirror assembly for large vehicles, such as trucks and vans,said exterior rearview mirror assembly comprising: a reflective mirrorelement having a reflective surface of at least 50 square inches; asupport bracket being adapted for mounting to a vehicle; a mirror casingsecured to said support bracket, said mirror casing housing said supportbracket and said reflective mirror element therein; and an electricactuator mounted to said support bracket by a plurality of fasteners,said reflective mirror element being supported by said electric actuatorin said casing, said electric actuator having an actuator housing and amovable member, said actuator housing having a base and a cover, saidmovable member provided at one side of said actuator housing, said basehaving a projecting rim, said movable member extending into saidactuator housing between said rim and said cover and being frictionallyengaged by said rim and said cover, said base having a planar raisedperipheral surface extending around said fasteners inwardly of said rimand at an opposed side of said actuator housing from said movableportion, and said support bracket providing bearing contact for at leasta portion of said peripheral surface of said housing, with said at leasta portion contacting said bearing contact whereby said mirror assemblyhas reduced vibration and improved stability.
 40. The mirror assembly ofclaim 39, wherein said support bracket includes a gasket providing saidbearing contact.
 41. The mirror assembly of claim 40, wherein saidgasket comprises a resilient pad, said resilient pad compressing atleast 10% when said actuator housing is mounted to said support bracket.42. The mirror assembly of claim 41, wherein said resilient pad has adurometer in a range of 12 to 18 Shore O.
 43. The mirror assemblyaccording to claim 39, wherein said support bracket includes a planarbearing surface, said planar bearing surface contacting at least 50% ofsaid peripheral surface.
 44. The mirror assembly of claim 43, whereinsaid planar bearing surface contacts at least 75% of said peripheralsurface.
 45. The mirror assembly of claim 44, wherein said supportincludes an adapter, said adapter providing said bearing contact. 46.The mirror assembly of claim 44, wherein said planar bearing surfacecontacts approximately 100% of said peripheral surface.
 47. The exteriorrearview mirror assembly according to claim 39, wherein said supportbracket comprises an elongated truss-like support bracket and furtherincludes an enlarged medial portion, said enlarged medial portionproviding said bearing contact.
 48. The exterior rearview mirrorassembly according to claim 47, wherein said enlarged medial portion issized at least as large as said peripheral surface of said housing.